Determination of Aminoglycoside Fungicide Validamycin A in Rice Plant by Quick, Easy, Cheap, Effective, Rugged, and Safe Approach Using Ultra High Performance Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry

Abstract

A rapid, simple, sensitive, and reliable method was developed for the determination of validamycin A residues in rice plants based on a modified quick, easy, cheap, effective, rugged, and safe extraction procedure using ultra high performance liquid chromatography-tandem mass spectrometry. The samples were extracted with methanol/ water (9:1, v/v) and cleaned-up with octadecylsilane, graphitized carbon black and primary secondary amine for the rice hull, rice straw, and brown rice, respectively. The mass spectrometry parameter optimization was performed in multi-reaction monitoring mode, and electrospray ionization in positive mode was selected. Recovery studies were performed in three matrices at three levels (10, 100, and 500 μg/kg) with average recoveries ranging from 77.7 to 94.3 % and relative standard deviations of less than 9.8 % (n = 5) for the analyte. The limits of detections (LODs) for validamycin A were below 0.40 μg/kg, and the limits of quantifications (LOQs) were below 1.32 μg/kg. The effects of different columns on the separation were also investigated. The method was successfully applied in a study of validamycin A residues in rice plants.